Permutation electric switch



Jan. 10, 1950 w. TATE ET AL PERMUTATION ELECTRIC SWITCH 2 Sheets-Sheet 1Filed Nov. 26, 1947 Jan. 10, 1950 N. L. TATE ET AL PERMUTATION ELECTRICSWITCH 2 Sheets-Sheet 2 Filed Nov. 26, 1947 w WW /W a/m 4w a AQ U 5E n/4 Patented Jan. 10, 1950 UNITED STATES PATENT OFFICE William LeonardTate, Liverpool, andArthur Aloysius Oakes, Nottingham, EnglandApplication November 26, 1947, Serial No. 788,246 In Great Britain March20, 1946 9 Claims.

This invention relates to a permutation electric switch which, whilesuitable for controlling electric circuits generally, is particularlyapplicable for controlling the ignition circuit on a motor car or likemotor road vehicle.

An object of the invention is to provide for the said purpose animproved permutation switch of the kind comprising a movable member anda plurality of rods operable, against resilient means such as springs,by means of push buttons WhlCh are identified by associated numerals,letters or other symbols, a selected plurality of said rods beingadapted when actuated in predetermined sequence to effect progressivemovement of a member which at the end of such movement closes theelectric circuit.

According to the invention, the improved permutation switch comprises amovable member, such as a plate, disc or the like, having a series ofslots therein, a plurality of push-button operated rods each slidablytraversing one of said slots and thereby limiting movement in oppositedirections of said member, switch means associated with the movablemember disposed to close the electric circuit by displacement of themember to one operative limit of its movement and to open said circuitby return of the member towards its opposite inoperative limit, aselected plurality of the rods being adapted when operated inpredetermined sequence to displace the member progressively to saidoperative limit, and the remainder of the rods being each adapted toreturn the member to its inoperative limit.

In the accompanying explanatory drawings a permutation switch isillustrated suitable for use on a motor car,

Fig. 1 being an elevation,

Fig. 2 a plan and Fig. 3 a linear developed elevation of the circularrow of push buttons for operating the switch.

Fig. 4a is a plan of the rotatable plate in the switch and Fig. 4 is asection on the line 4-4, Fig. 1.

Fig. 5 is a fragmentary View showing the position of the switch arm whenthe ignition circuit is open and the indicator or pilot light glowing,

Fig. 6 being a similar fragmentary view showing the position of theswitch arm closing the ignition circuit.

Fig. '7 is a fragmentary elevation of one push button providing awarning signal for closing the horn circuit of the car,

Fig. 8 being a side view of Fig. 7.

Fig. 9 is a view similar to Fig. '7 showing the push button depressedand retained in position closing the horn circuit.

Fig. 10 is a fragmentary elevation partly in section, and

Fig. 11 an inverted plan of a switch control for the indicator pilotlight.

Fig. 12 is a fragmentary elevation and Fig. 13 a plan of the horncircuit-closing switch actuated by lifting the engine bonnet of the car.

A permutation switch applicable for controlling the ignition circuit ofa motor car is illustrated in the accompanying drawings, and comprises aframed casing consisting of three plates I, 2, 3 spaced apart andconnected by posts 4, the upper and. lower plates I and 3 beingpreferably of fibre or some insulating material. The framed casing isset in an aperture in, say, the dashboard 5 of the car, and mounted toslide transversely in the three plates l, 2, 3 are a number of pushbuttons 6 under spring controls I, and each having a collar la urged bythe spring against the underface of the upper plate l. Rotatably mountedon a pivot 8 in the casing is a disc 9, having therein a number ofseparated slots [0 circularly arranged, Fig. 4a. The rods of the pushbuttons 6 slide in the slots l0 when th buttons are depressed and theparts I i of the rods engaging the slots are of square section, Fig. 4,so that they cannot rotate in the slots, and each rod is provided with awedge or like shaped fin 12 or l3, the inclined side of which is adaptedwhen depressed to engage any edge of the slot which it overhangs and soimpart to the disc 9 a certain angular movement.

The rods are in two groups, the fins [2 of one groupwhich may be termedthe effective group-- pointing in one direction round the disc 9 and thefins I3 of the other or ineffective group pointing in the reversedirection, so that while operation of any rod of the l3 group impartsclockwise movement to the disc 9, any rod of the I2 group impartsanti-clockwise movement. The push buttons 6 by which the rods areactuated carry various indicating numbers as shown, and/or letters, andby pressing the efiective buttons consecutively in a known code sequencethe disc 9 will be rotated by the fins l2 step by step anduni-directionally to an operative limiting position to actuate a switchclosing the ignition circuit of the car.

In the example given the effective buttons of the code for closing theswitch are those numbered 9, 4, 1, '7 to be operated in that sequence,and in order that the movable disc 9 cannot be operated by depression ofthe effective push button-s in other than the correct sequence theirWedge shaped fins I2, except the fin on the rod of the button numbered 9which is to be operated first in the correct code sequence, all have astep 14 at the fin base which prevents th ir being depressed until thewedge fin of the rod to be previously operated in the correct sequencehas been already operated. With this object the fin l2 of the rod of thebutton numbered 9 to be first operated in the code sequence terminatesgradually into its rod, the maximum projection of the oblique edgecorresponding to the extent of the base step M of the fin E2 on thesecond rod button numbered 4 of th code sequence, the maximum projectionof the oblique edge ii of such second fin determining the extent of thebase step M on the third rod button numbered 1 of the code sequence, andso on, so that prior depression of the second or third buttons in thecode is prevented b the base steps of the fins overhanging the operativeedge beneath of the slot in the movable disc 9, until such edge hasfirst been moved clear of the base step by rotation of the disc 9 by arod previously operated in correct sequence.

In this way if the effective push buttons be depressed in other than thecorrect code sequence the plate cannot be rotated. The fins 63 of theinefiective buttons engage the left hand edges, Fig. 3, of the slots ISin which they slide while the effective buttons engage the right handedges of their slots and the projecting extent of every fin IS in theineffective group is such that when. depressed they each move therotatable plate angularly to the same extent and not step by step as dothe effectiv buttons. Consequently if the device be operated Withoutknowing the correct code sequence any chance sequential op eration ofcertain of the effective buttons moving the disc 9 in the switch closingdirection will be neutralized by operation of any one button of theineffective group, the disc being rotated in a contrary direction to itsinoperative limiting position.

The correct and complete operation of the disc 9 by the known codesequence of buttons moves the disc, as indicated by the arrow, Fig. 6,to a position such that a roller 40 or other contact on the disc engagesthe T-head it of a rocking arm ll pivoted at IS on the lower plate 3 andthrows over the arm to engage one contact 12 of a switch and close theignition circuit a of the car. If, however, any one of the ineffectivepush buttons be operated, the disc 9 will be rotated in the oppositedirection indicated by the arrow, Fig. 5, the roller 41'] throwing overthe arm I? to the other switch contact 8 9 opening the ignition circuitand closing the circuit 1) of a pilot or indicator light at someconvenient position on the dashboard.

The pilot 26] is thus normally on when the ignition circuit is open, butout when the switch is closed. The rocking arm ll of the switch isspring-controlled so that it tends normally to move to the position Fig.5 interrupting the ignition circuit and closing the pilot light circuit.When, therefore, the effective buttons of the code have been correctlydepressed in sequence, the pilot light 29 will be cut out, theextinguishing of which thus denotes that the ignition circuit is closed,so that if the mechanism be in correct working order it is impossiblefor the ignition circuit to be closed and the pilot light to be on atthe same time.

The contact head It of the switch arm H may be curved or recessed forengagement by the roller 40 to obtain a more eifective closing andopening action of the switch.

Certain of the button rods in the efiective group carry contacts which,when such rods are depressed, engage other contacts, thus closing thecircuit of the electric horn of the car to give an audible alarm thatthe device is being tampered with.

Such an arrangement is illustrated in Figs. 7 to 9 where the sliding rodll of one of the push buttons 6 carries a bent spring contact 2i adaptedto engage a contact 22 carried on an insulating arm 23 on the rotatabledisc 9. Normally the relative positions of the two contacts would beshown in Fig. '7 but if the button 6 be depressed the contact 2!ultimately clicks beneath the contact 22 to close the circuit 0 of thehorn 24, Fig. 8. The hooked formation of the contactcarrying arm 23retains the contact 21 in engagement as the rod rises under its springcontrol ll, so that the horn will continue to sound until the disc 9 isrotated by pressure of certain buttons of the code sequence carrying thecontact 22 sidewise and moving it clear of contact 2! and opening thhorn circuit.

The circuit of the pilot light 26 being normally closed when theignition circuit is open, in order to avoid continuous illumination ofthe light at times other than when required an additional control switchmay be provided, Figs. 10 and 11, consistin of a tubular member 25 inwhich the pilot light 25 is housed and which is rotatable in the fibreor other insulating plate I of the device, the tubular housing having aprojecting switch arm 28 movable into engagement with a fixed terminalcontact 21 when the light is required, but by turnin the member 25 thecontacts are separated to open the circuit.

With a view to preventin unauthorised shortcircuiting of the ignitionswitch by unauthorised lifting of the car bonnet or tampering with anyother movable part of the vehicle and connecting the circuit wires toenable the car to be driven away a device shown in Figs. 12 and 13 maybe provided. This consists of a contact 28 sliding in an insulatingblock 29 and urged by a spring 3t, one wire of the horn circuit 0 beingconnected to this sliding contact. Another fixed contact 35 insulated ina block 32 is connected to the other wire of the horn circuit. Normallythe contacts 28, iii are separated as shown and the horn circuitinterrupted by an insulating member 33 carried on the lower edge of aside wing 34 of the engine bonnet. If the bonnet be liftedunauthorisedly the contact 28 will make contact with the contact 3! toclose the circuit 0 and sound the horn. Means may be provided forrendering the horn circuit closing action of the contacts 28, 35inoperative, when desired, and such means may be operated by depressingcertain of the effective buttons 6 of the device.

Other circuit closing buttons may be provided in the ca sing if desired,one 13, Fig. 2, for the side lights and another 44 for the headlights.

Any desired variation of the code number or lettering may be obtained bychanging the position of the push buttons and rods and in this way thetamper-proof effectiveness of the device rendered very secure.

What we claim is:

l. A permutation switch for controlling an electric circuit, comprisin amovable switch-actuating member having a series of slots therein, aplurality of push-button operated rods each slidably traversing one ofsaid slots and thereby limiting movement in opposite directions of saidmember, switch means operable to close the electric circuit by saidmember on its displacement to the one operative limit of its movementand to open the circuit by the member returning towards its opposite,inoperative limit, a selected plurality of the rods having each one of aseries of progressively larger wedge-shaped fins extending towards saidoperative limit and engageable in the slots to effect successivelygreater step-wise displacements of the member to said operative limit,and the remainder of the rods having each a wedge-shaped fin extendingtowards said inoperative limit and engageable in on of the slots toeffect displacement or" the member towards its inoperative limit.

2. A permutation switch for controlling an electric circuit as claimedin claim 1, in which each of the progressively larger fins has at itsbase and bearing on the movable member a step which corresponds inextent to the maximum projection of the fin on the rod having prioroperation in the permutation sequence, such base step preventingoperation of any of said selected rods out of its predetermined sequence.by overhanging the edge of the slot in which its rod slides until suchedge is moved clear of the base step upon displacement of the member byoperation of the rod previously actuable in the sequence.

3. A permutation switch for controlling an electric circuit as claimedin claim 1, said switch means being a two-throw switch operable to closean engine ignition circuit by displacement of the movable member to itsoperative limit, and alternatively operable by displacement of saidmember from said limit to energise a pilot light indicating that theignition switch is open.

4. A permutation switch for controlling an electric circuit as claimedin claim 1, including an electric contact on at least one of the rodsand another contact on the movable member, said contacts being mutuallyengageable in selfretaining circuit-closing connection by operation ofsaid rod and disengageable by displacement of said member underoperation of one of said selected plurality of rods.

5. A permutation switch for controlling an electric circuit, comprisinga turnable switchactuating disc having a circular series of slotstherein, a plurality of push-button operated rods each slidablytraversing one of said slots and thereby limiting movement in bothdirections of the disc, switch means operable to close the electriccircuit by said disc turning to the one operative limit of its movementand to open the circuit by the disc returning towards its opposite,inoperative limit, a selected plurality of the rods having each one of aseries of progressively larger wedge-shaped fins extending towards saidoperative limit and engageable in the slots to effect successivelygreater step-wise displacements of the disc to said operative limit, andthe remainder of the rods having each a wedge-shaped fin extendingtowards said inoperative limit and engageable in one of the slots toeffect displacement of the disc to said inoperative limit.

6. A permutation switch for controlling an electric circuit as claimedin claim 5, including an electric contact on at least one of the rodsand another contact on the turnable disc, said contacts being mutuallyengageable in self-retaining circuit-closing connection by operation ofsaid rod and disengageable by turning of said disc under operation ofone of said selected plurality of rods.

7. A permutation switch for controlling an electric circuit, of the kindcomprising a movable switch-actuating member, a, plurality ofpush-button operated rods, means on said rods engageable with abutmentson said member under sequential operation of the rods to effectsuccessively greater displacements of the member to an operative limit,and switch means operable by the member at said limit to close theelectric circuit, having in combination a further plurality of like rodsand in assocation with each of said rods a projection engageable underoperation of the rod with one of the abutments on the member to effectpositive displacement of the movable member from its switch-actuatinglimit.

8. A permutation switch for controlling an electric circuit, of the kindcomprising a turnable switch-actuating disc, a plurality of pushbuttonoperated rods, means on said rods engageable with abutments on said discunder sequential operation of the rods to eiiect successively greaterangular displacements of the disc to an operative limit, and switchmeans operable by the disc at said limit to close the electric circuit,having in combination a further plurality of like rods and inassociation with each of said further rods a projection engageable underoperation of the rod with one of the abutments on the disc to efiectpositive displacement of the disc from its switch-actuatin limit.

9. A permutation switch for controlling an electric circuit as claimedin claim 8, wherein said abutments on the disc are a circular series ofslots each traversed by one of the rods, and each of said projections onsaid further plurality of rods is a triangular fin engageable camwisewith an end of the slot traversed by its associated rod.

WILLIAM LEONARD TATE. ARTHUR ALOYSIUS OAKES.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name 7 Date 993,378 Jepson et a1 May 30,1911 1,568,483 Tolbert Jan. 5, 1926 1,704,582 Stephenson Mar. 5, 19291,810,399 Horni June 16, 1931 2,442,766 Garvin June 8, 1948

